texinfo, version 3.9

Adapted from the texinfo file:

Texinfo is a documentation system that uses a single source file to
produce both on-line help (and other information) and a printed
manual.  This means that instead of writing two different documents,
one providing on-line information and the other for a printed manual,
you need write only one document.  When the system is revised, you
need revise only one document.  Using the texinfo package, you can
read the on-line help, known as an Info file, with the Info
documentation-reading program or format a manual for printing.  Many
of the packages supplied by Ready To Run Software, Inc include texinfo
style documentation.